Children's project "Why is snow white?" Interesting facts about snow for children Why are snowflakes white?

Snow is a sign real winter. It is formed when small raindrops freeze. Fluffy white snow- a real miracle. Children make snowmen out of it, play snowballs with them, and northern peoples build their homes from snow. A thick layer of snow warms the ground. It does not allow frosty air to approach it, and maintains a positive temperature deep in the soil.

What is snow and how is it formed?

Scientifically speaking, snow is a type atmospheric precipitation. This means that snow falls from the sky as frozen rain. The snow is cold, white and fluffy. It consists of individual snowflakes that look like six-pointed stars. I wonder how snow is formed?

The first condition for snow to appear is cold. The temperature at which water turns into ice is 0ºC. When it gets cold outside, the water in puddles and lakes becomes covered with ice (freezes). At this time, rain clouds freeze in the sky. Raindrops turn into snow in them.

The second method of snow formation is scientifically called evaporation. Listen to how it happens. If you wash your clothes and hang them outside in winter, the wet sheet will first freeze and become hard. After a few days, the sheet will turn into a soft, dry cloth. What happened? First, the water in the sheet turned into ice. It happened pretty quickly. Then the ice began to evaporate: small microscopic pieces of ice came off the sheet and rose into the sky. These pieces of ice were so small that, looking at the drying sheet, we did not notice their flight.

Why is it snowing?

Many small pieces of ice are found in the heights of the sky. There they gather into a snow cloud. There are so many snowflakes in the cloud that they join together several at a time. Several small ice stars make a large snowflake, which becomes too heavy and falls down. This is how the snow begins.

It doesn't take one wet sheet to form a big snow cloud. Many tiny pieces of ice rise into the sky from a frozen lake, puddle or river. There they gather into large snow clouds.

The wind can carry such a cloud far. For example, where there is no frost. Thanks to the wind, snow can fall even in places where lakes and rivers have not yet frozen.

How are snowflakes formed?

Have you ever seen a snowflake under a microscope? It looks like a six-pointed star. Each end of the star consists of a white branch on which small white twigs grow.

These branches are scientifically called crystals. They intersect in the middle of the snow star. Each snowflake begins to grow from the center - from the place where the snow branches intersect. The growth of a snowflake is similar to the growth of a tree: six trunks grow from the center, on each of which branches begin to grow. Stars can have different branches (long or short, thick or thin), but only 6 large branches always grow in a snow star.

When water freezes in a river or puddle, it turns into ice. The stars in the ice are located close to each other. When fog or cloud freezes, the stars are located at some distance from each other. If there are too many stars, they join together several at a time and fall down. This is how snow pours out of a cloud and covers roads, houses and fields. Adults call the fall of snowflakes snowfall.

Why does the snow squeak underfoot?

If it is slightly frosty outside (-2 or -3 ºС), then there is a lot of water in the fallen snow. They say about this kind of snow that it is “wet”. It’s easy to make snowballs and a snow woman from wet snow, and build “fortresses.”

When the frost gets stronger (air temperature drops to -5 or -10 ºC), the snow freezes harder and becomes dry. It’s impossible to make a snowman out of dry snow, but it creaks loudly underfoot. Why does dry snow squeak?

Each snowflake looks like a small star. If we step on the snow, the branches in the icy snowflakes break. So, when breaking many snowflakes, a crunch and creaking is formed.

Snow creaks with any pressure:

• if it was stepped on;
• went skiing;
• went sledding.

The snow stops creaking only when it becomes almost warm (the air temperature approaches 0ºC). Or when it was rolled heavily (this happens on slides, where the snow rolls away and turns into ice).

When does the snow squeak very loudly?

Snow can creak louder or quieter. When does the creaking of snow become very loud?

This happens in severe frost. For example, in the far north, at -50ºC, the crunch of snow becomes so loud that it can be heard on the next street.

With warming, when the air temperature approaches 0ºC, the crunching disappears completely. The snowflakes become soft, drops of water appear on their icy branches, which prevents the icy stars from creaking.

Scientists are conducting interesting experiments with frozen water. It turns out that water hears us and reacts differently to kind and rude words. This is what the next video is about.

Each of us has thought about why snow is white, and not black, blue, red or something else, at least once in our lives. Most often, the question “why is snow white” is asked by children to their parents, but not even all adults know the answer to this question.

To understand why snow is exactly this color, you first need to define the concept of color in general. What is color from a physics point of view?

We are surrounded by electromagnetic radiation, also called electromagnetic waves . These waves are everywhere, but most of these waves are invisible to the human eye.

The visible part electromagnetic radiation perceived as color. From a scientific point of view, any color is a wave electromagnetic radiation, which is perceived human vision and is converted into a color sensation.

The primary source of electromagnetic radiation for us is the Sun. Sun rays, that is, waves, contain the entire spectrum of visible radiation, that is all basic seven colors- red, orange, yellow, green, blue, indigo, violet.

The colors of the visible spectrum merge to form white.

Some items completely absorb light waves- we see them black, other items allow the sun's rays to pass through, that is, they are transparent. This is glass, water or ice.

Have you ever read fairy tales about living and dead water? Then you will be interested to know what it is really like to use them and much, much more!

Do you know what density equals? sea ​​water and why is it easier to swim in it than in a river one? Very interesting information is located, learn something new for yourself!

Most objects in our world absorb some of the rays and reflect some. For example, you can take an ordinary leaf from a green tree.

What leaf green tells us that from the visible spectrum solar radiation it reflects rays of green light, and that's all absorbs the rest.

An orange absorbs all rays except orange, a red poppy absorbs all but red, and so on.

The following can be said about snow - it reflects all the rays of the visible spectrum, so we see it white, that is, the way light from the Sun appears to us.

Why is snow white and not transparent? ^

And a little more science. Someone will ask why the snow is still white and not transparent. Snow is essentially water, only in a different state of aggregation.

Water is a liquid, ice is solid, snow is a loose substance consisting of individual ice crystals. Water and ice are transparent.

But in fairness, it should be noted that in nature there are no absolutely transparent bodies, like there are no absolutely black and absolutely white bodies. Even glass is not completely transparent.

Be that as it may, water or ice has a more or less smooth surface, which affects the passage of sunlight through it.

Passing through the thickness smooth ice, the rays are not absorbed and practically not refracted, most of them are transmitted, and a smaller part is reflected from the surface.

Snow is very different in its properties from ice, it's loose and not smooth at all.

To study the properties of snow in more detail, just look at a snowflake. Each snowflake is unique and has its own pattern.

But what all snowflakes have in common is that they are not smooth, but consist of many faces, that is, tiny surfaces located at an angle to each other.

A mass of snow consists of many such snowflakes that are attached to each other. Falling on a snowy surface, sunlight is refracted many times and reflected from the edges of snowflakes.

Ultimately, most of the sun's visible radiation is reflected from the snow. Moreover, as already mentioned, rays of the entire visible spectrum are reflected, which is why we see snow as white.

Snow can be compared to crushed glass or diamonds. If we imagine a huge scattering of diamonds, then it will also seem white and sparkling to us.

Perhaps everyone has noticed that in bright sunlight in winter, the surface of the snow sparkles and shimmers with all the colors of the rainbow.

So, it is the incident sunlight that is refracted and splits into individual spectral colors. That's why we see multi-colored sparkles on white snow.

Do you know what it is equal to and why it differs from the boiling point of fresh water?

Read what dew point is, how important it is and how it can be calculated, keep your home comfortable!

When snow melts, it forms special kind water - melt. How you can get it at home, how healthy it is and how it is used, read here:
, this is very interesting!

Our Ksyusha has become a bitch. And mom and dad became walking mini-encyclopedias. Therefore, we decided to create the same reasons to help parents new section“ ” and publish answers to the most common children's questions in it. We will try to adapt all the answers as much as possible for preschool children, so that it is easier for parents to explain to them the complex laws of nature.

It's winter now and therefore, of course, questions about why are in the TOP :) Therefore, we publish our answers to the snowiest questions.

What is snow?

Snowflakes are formed in the same way as raindrops: water evaporates from the seas and oceans and rises to the sky, where it cools and collects into droplets. When it is very cold, water droplets freeze into ice crystals. They fall to the ground in the form of snow. The melted snow evaporates or flows into streams, from where it again begins its path to the sky.

Why is snow white?

If snowflakes and droplets are of the same nature, then why are the droplets transparent and the snowflakes white? The fact is that each individual snowflake is transparent in itself, but together they fall to the ground in a chaotic manner and form a loose mass. Snowflakes lie to each other at different angles. Sunlight is reflected first in one snowflake, then in another, and so on, until it is directed back. It turns out that snow completely reflects sunlight, and since the rays of the sun white, then the snow is white. If the rays of our Sun were yellow and red, then the snow would also be yellow or red. At sunset or sunrise, when we see the pink rays of the sun, the snow also turns pink.

Why do snow and ice melt from salt?

Snow and ice are water that freezes (becomes solid) at 0 degrees Celsius. If you add salt to water, you get brine, which freezes at temperatures below 0. If we sprinkle salt on ice or snow, we will make it melt, since salt dissolves in water and lowers its freezing point.

First, the ice around the salt crystal will melt, and then the melting process will spread further from this point.

Which snow melts faster?

Dirty snow melts faster because:

1. There are also salts in the mud, which speed up the process of snow melting.
2. Mud is usually dark, which means it absorbs the sun's rays and, as a result, quickly heats up, warming the snow in its wake.

Is it possible to eat snow?

Snow tends to collect dust. City dust, in addition to ordinary natural dirt and bacteria, contains many heavy metals and other toxic substances that are very dangerous for humans. By eating snow, a person absorbs all these toxic substances and puts his life at risk of poisoning.

High in the mountains, pure snow falls without dangerous impurities, but such water is also unprofitable for the body, since it lacks the most important salts that are usually found in drinking water. There is only one conclusion: eating snow is not only unhealthy, but also dangerous to health.

Are there any identical snowflakes in the world?

More than a hundred years ago, when the first cameras first appeared, one man nicknamed “Snezhika” decided to photograph snowflakes under a microscope. He took 5,000 pictures, but not a single snowflake pattern was repeated. Many years have passed, and scientists are still arguing: are there any identical snowflakes. They even created 2 twin snowflakes in their laboratory, but this still did not put an end to their dispute. Having started another study, scientists came to the conclusion that snowflakes may differ not only in their external pattern, but also internal structure. This means that even if snowflakes are identical in appearance, most likely their internal structure is still different.

Shadrina Ekaterina

Goals and objectives of the project, information about the formation of snow and ice, experimental experiments.

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Research project on the topic: “Why is snow white.” Completed by a 3rd grade student of the Municipal Educational Institution “VSOSH”: Ekaterina Shadrina Project leader teacher primary classes Municipal educational institution "VSOSH": Mironova Elena Vladimirovna

White fluffy snow swirls in the air and quietly falls to the ground and lies down. And in the morning the Field turned white with snow, as if everything had been covered with a shroud.

Statement of the problem. Winter has come. It became cold outside. One morning I woke up and looked out the window. I saw that everything around: the ground, trees, roofs of houses, became white. It was the first snow. I thought: “Why is snow white?”

Project goal: Study and conduct experiments to answer the question “Why is snow white?”

Project objectives: Study literature that talks about snow. Prove experimentally “Why is snow white?”

Object of study: snow. Hypothesis: Suppose that the white color of snow is due to the reflection of light. Research methods: 1. Study of literature on the topic. 2. Observation of the research object. 3. Conducting experiments. 4. Analysis of the results and conclusions from the study.

Introduction Snow is frozen water. What color is the ice? None. He lets everything pass through him sunbeam and remains colorless. Each individual snowflake would also freely transmit a ray of sun through itself and would also be colorless, like ice. But the snowflakes fall on each other in disarray. Together they become opaque, do not allow rays to pass through them, but, on the contrary, reflect them into the eyes. And that's why snow appears white.

Conclusion: each snowflake is a collection of small pieces of ice; snowflakes lie differently; snowflakes reflect light in different sides.

Experience No. 1. I took the transparent one plastic bag. I cut it into small pieces. Each piece is a “snowflake”.

I put all the pieces in a transparent glass. They were positioned differently.

Result: “snow” in a white glass.

Experience No. 2. She poured water into a glass and put it in freezer. The water turned into transparent ice.

Mom broke the ice into small pieces. He turned white.

Summary and Conclusion Conclusion Pieces of plastic bag and pieces of ice are individually transparent. Light passes through them and is not reflected. When the pieces of the package lie chaotically (in different ways), they reflect light in different directions. Conclusion Snow is white because each snowflake reflects light in different directions. In scientific language - “light is scattered.” This makes the snow white.

Sources of information: Children's Encyclopedia. "I'm exploring the world." – M.: AST Publishing House LLC, 2001.-557 p.: V. A. Markin. Photos from the home archive, taken during the experiments - 2014 http://otvet.mail.ru/question/62950897 - photograph depicting snowy trees. http://www. adobetutorialz. com / articles /2909/1/ We - wish - you - a - Merry - Christmas - illustration - template for presentation computer science teacher Irina Borisovna Kurbanova, GOU Secondary School No. 594, St. Petersburg, website: http://pedsovet.su/

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Municipal educational institution "Voskinsky secondary school"

Research project on the topic:

"Why is snow white?"

Completed by a student

3rd class

Municipal educational institution "VSOSH":

Shadrina Ekaterina.

Project Manager

primary school teacher

Municipal educational institution "VSOSH":

Mironova Elena Vladimirovna.

2014

• Statement of the problem.
• Project goal.
• Project objectives.
• Object of study.
• Hypothesis.
• Research methods.
• Literature.

Statement of the problem.

White fluffy snow

Spinning in the air

And the ground is quiet
Falls, lies down.
And in the morning there is snow
The field turned white
Like a veil
Everything dressed him.

Winter has come. It became cold outside. One morning I woke up and
looked out the window. I saw that everything was around: the earth, trees, roofs of houses,
turned white. It was the first snow.
I thought: “Why is snow white?”

Project goal:

Studying and conducting experiments to answer the question “Why is snow white?”

Project objectives:

1. Study literature that talks about snow.
2. Prove experimentally “Why is snow white?”
   

Object of study: snow.

Hypothesis: Let's assume that the white color of snow is due to the reflection of light.

Research methods:
1. Studying literature on the topic.

2. Observation of the research object.

3. Conducting experiments.

4. Analysis of the results and conclusions from the study.

Introduction

Snow is frozen water. What color is the ice? None. It transmits the entire ray of sunlight through itself and remains colorless. Each individual snowflake would also freely transmit a ray of sun through itself and would also be colorless, like ice. But the snowflakes fall on each other in disarray. Together they become opaque, do not allow rays to pass through them, but, on the contrary, reflect them into the eyes. And that's why snow appears white.

From my observations while studying literature, I learned that any snowflake has the shape of a six-pointed star. Regardless of the shape of the snowflakes, they are all white. And the snow is white, white, and if the sun is shining, it becomes dazzling white. Why? A snowflake consists of crystals of ice and air; light falling on the rays of a snowflake is reflected from them, scattered and perceived by us as white. And when a ray of sunlight hits the crystals, it is reflected from it and blinds our eyes. I decided to conduct experiments to prove that snow is really white.

Conclusion:
- each snowflake is a collection of small pieces of ice;
-snowflakes lie in different ways;
-snowflakes reflect light in different directions.

How I conducted the experiments

Experience No. 1.

I took a transparent plastic bag. I cut it into small pieces. Each piece is a “snowflake”.

I put all the pieces in a transparent glass. They were positioned differently. Result: “snow” in a white glass.

Experience No. 2.

I poured water into a glass and put it in the freezer. The water turned into transparent ice.

Mom broke the ice into small pieces. He turned white.

The question of why snow is white is familiar to every person since childhood. But not all children, and even adults, know the correct answer why small snowflakes are blue or green. Everyone knows that snow is frozen water, or rather ice. But since ice is transparent and capable of transmitting light through it, why are the snowdrifts that cover the ground far from being opaque, but having a very distinct color?

In past centuries, when there were no such developed technologies that made it possible to study all natural processes, scientists struggled with the question of why snow is white. However, the answer was never found. Only when the entire process of creating snow from the very beginning to the end became clear, some guesses about the “snow-white cover” appeared.

It all starts with the fact that under the influence of warm sunlight Water from rivers, lakes and seas turns into steam and rises high into the atmospheric layers where permafrost predominates. Steam, in turn, having the properties of liquid water, due to the high subzero temperature, begins to solidify and turns into ice crystals. These are snowflakes that are ready to fall to the ground over time. For the most part, in places where it is warm, pieces of ice fall in the form of wet precipitation, melting while still in the air.

How snow is formed is now clear, but why, when it falls to the ground, does it suddenly turn white?

The question is relevant, because snowflakes, while still in the air, have the same properties of transmitting light through themselves as ice. But one thing should not be forgotten: the edges of the lenses are located at chaotic angles, which randomly refracts sunlight, and they do not absorb it, but transmit it further. And when the snowflakes gather into a “snow-white blanket,” the rays of the sun, refracted from one snowflake to another, pass through the entire cover. Many rays are reflected into our eyes, which is why often when you look at the snow you have to squint. Sunlight is too bright to be perceived by unprotected eyes.

But it is not entirely correct to ask the question of why snow is white, because it is not always “clean”. People see him like this only when the rays of sunlight fall on him. For example, at sunset it may turn pinkish, and in the light of a yellow lantern it may be slightly grayish, just like in cloudy weather.

Changes in the color of the snow are also possible in the air layers, when the snowflakes are just beginning to “fall to the ground.” For example, various pollen from trees and flowers, dust from arid land rises and meets grains of snow in air currents. If such snow does not have time to melt and is preserved by a small cover, then its color will certainly have different shades. Under these conditions, asking why the snow is white is inappropriate.

However, snowflakes are not just pieces of ice flying chaotically downwards, which for unknown reasons decided to cover the ground with a “white blanket”.

The main properties of snow are to protect the earth from the cold by covering it with a thick blanket. Yes, yes, it would seem paradoxical to warm and preserve the crop and soil from freezing, but it is true. It has poor thermal conductivity, allowing it to contain heat escaping from the ground and create a “thermal cushion”. It’s not for nothing that igloos were built by residents of the far north. Ice, like snow, holds heat well, creating unique favorable conditions for life.

One should not lose sight of the fact that the size of snowflakes depends on weather conditions outside the window. If it’s cold enough, the ice flakes are small, almost invisible. But if the sun is shining and the air is not so cold, then the size of a snowflake can reach several centimeters. So, in 1944, ten-centimeter “grains of ice” fell in Moscow.